"Al2024 alloy is known as one of the most used aluminum alloys, especially in aerospace industry. However, it does not have desirable fricative properties just like other aluminum alloys. We improved the properties of the alloy by creating a nanocomposite layer on its surface," Babak Zahmatkesh, one of the researchers, told the news service of Iran Nanotechnology Initiative Council's website.

After preliminary studies, the researchers designed an appropriate tool for the friction stir process and optimized the parameters of the process. Then, they produced Al-10% Al2O3 nanocomposite powder through mechanical alloying and applied the powder on the surface of the base metal during a plasma heat spraying process.

The combination of plasma heat spraying process and friction stir process used in this research solves the problems in the previous methods during the coating with strengthening particles.

In the previous methods, there were observed various problems such as severe aggregation, impossibility of the extension of the strengthened zone on the plate surface, non-homogeneity in the thickness of the strengthening layer, formation of pores and limitations in the thickness of the strengthened layer.

"The results show that the strengthening particles have diffused homogeneously into the sub-layer and the average thickness of the nanocomposite layer is 600 micrometers," Eng Zahmatkesh said about the results obtained in the research.

"In addition, the nanocomposite sample has a higher resistance against friction in comparison with the base metal to the extent that the amounts of weight reduction at the end of the friction experiment (1000 m) were 37.7 mg for the base metal and only 4 mg for the nanocomposite sample. The results of micro-resistance test show a noticeable increase in the hardness of nanocomposite compared to that of the base metal," he added.